Casting machine



P. E. SCHWARZ AND T. D. SALMON.

CASTING MACHINE.

APPLICATION FILED MAR.23,1922.

11,424,595 Patented Aug. 1, 1922.

PAUL E. SGHWARZ AN D THOMAS D. SALMON, 0F PHILADELPHIA, PENNSYLVANIA.

CASTING MACHINE.

Application filed. March 23, 1922.

T 0 all whom it may concern:

Be it known that we, PAUL E. SCHWARZ and THOMAS D. SALMON, citizens of the United States, residing in Philadelphia,

for the molds or investment rings, particu-' larly designed to receive any of several rings of different dimensions.

\Ve also desire to provide a casting machine including a cylinder and piston, with means for automatically locking said piston in the position in which it is moved in order to cause pressure to be applied to a body of molten metal, so that there shall be no possibility of back flow of air or of the formation of air bubbles until after the metal has solidified.

Our invention further contemplates novel means for preventing solid material passing to the interior of the cylinder, together with means whereby such foreign material may be conveniently removed from a pocket in which it is permitted to collect.

These objects and other advantageous ends we attain as hereinafter set forth, reference being had to the accompanying drawings, in which,

The figure is a longitudinal vertical section of a casting machine constructed in accordance with our invention.

In the above drawings 1 represents a cylinder casting having a laterally extended supporting base portion 2, one end of the cylinder being permanently closed and the other having a removable head 3. Within said cylinder is mounted a closely fitting piston 4 having connected to it a. piston rod 5 which extends through a central opening in the head 3 and has its outer end pivotally connected to an operating lever 6. The lower end of the latter is pivotally connected to one end of a link 7, which in turn is pivotally connected to the base 2 of the cylinder Specification of Letters Patent.

Patented Aug. 1, 1922.

Serial No. 546,193.

casting, and said lever is extended upwardly above the piston rod, having its upper end shaped as a hand hold 8 to permit of its convenient operation. The opposite or permanently closed end of the cylinder has an integral boss 9 formed adjacent its upper por tion and this is formed with a vertically extending, substantially cylindrical cavity opening through a passage 10 into the upper part of the cylinder. The lower end of this passage is normally closed by a conveniently removable plug 11 and its upper end has threaded or otherwise attached to it a cup 12 formed with a central, vertically extending passage 13 opening into the cylindrical cavity of the boss 9.

Concentric with this passage are a series of plane annular faces 14, 15 and 16 arranged in stepped relation and designed for the reception of the corresponding plane lower faces of investment rings or molds of different diameters, the cup having an upwardly extending peripheral flange 17. Within the cylindrical cavity of the boss 9 is mounted a cylindrical wire screen 18 conveniently removable after the plug 11 has been removed, and the arrangement is such that this screen not only effectually prevents solid matter entering the passage 10, but also is positioned to collect such solid material or particles in its lower part below the entrance to said passage.

The head 3 of the cylinder has formed in it an air relief passage 19 from the interior of the cylinder and in the present instance we have formed in line with a portion of this passage a cavity in which is operable a plunger 20 whose lower end is designed to enter a recess 21 in the piston rod 5 when this has been moved to a position in which the piston 4 is immediately adjacent the head 3. This plunger is at all times pressed toward the piston rod by a spring 22 and has on its outer end, which projects above the top of the cylinder head, a cap or head 23 to permit of its being drawn upwardly against the action of its spring.

Under conditions of use an investment ring or equivalent structure containing or carrying a mold, is mounted. in the cup 12 so that its lower face engages and makes substantially air tight contact with one of the flat faces 14, 15 or 16. With the piston in the position illustrated in the drawing, a body of metal is melted upon or immediately adjacent said mold and when said metal is at the right temperature, the operating handle 6* is drawn to the left until the l i i plunger enters the recess 21 in the piston rod. The resulting movement of the piston exhausts the air from the right hand end of the cylinder so that the atmospheric pressure acting on the molten metal forces it into a suitably prepared openingin the mold and into the cavity or cavities thereof. Obviously the plunger 29 looks the piston in its given position so that thereis no possibility of back pressure upon theinold from the cylinder which might form air bubbles in the casting. I v

During the above described operation of the piston the airothervviseconfined between it and the head 3 escapes through the pas sage 19 so that it does not interfere' ivitli the operation. Any particles of solid material drawn intov the passage 13 are caught in the cavity of the boss 9 from which they m y b removed from time to time byremoving the plug- 11; the screen 1 8 effectually preventing such particles from passing into the cylinder. When desired for further operation the piston is released by drawing out the spring plunger 20, after which it may' be returned to the position shown in the drawing, ready foranotherstroke, v l v v It is particularly to be noted that the above. described device isQrela'tively simple and rugged in construction anddoes not include or require valves of any kiiidf For this and" other-reasons it is reliable and capable of producing uniformly perfect cast-- ings, havin-g notendency to get out or order and being easily cleared, as above described.

We claim:

1. The combination in a casting machine of a cylinder casting including a hollow box communicating .vvith the interior or the casting; a mold-supporting cup mounted on said box having a passage communicating with the cavity thereof; a removable plug. closing the lower part of said cavity; a screen in the cavity for preventing solid material passing into the cylinder casting; a piston lll tlle cylinder casting; and means for actuating said piston.

2. The (:o'n ibination in a casting machine of a cylinder having a boX connected to its interior and formed With a cylindrical cavity therein; substantially cylindrical screen in said cavity positioned to prevent solid material passing into the cylinder; a plug normally closing the cavity of said box;

rod for actuating the piston; a hollow box formed to constitute a trap at one end of and communicating with the upper part or the cylinder; 'a' closure for an opening into the box and a cup tor a dental mold removably mounted on and having a passage connected tothe nter or 0t said box. 1 fl. The combination in a casting machine of a cylinder casting including a hollow box communicating With the interior ofthe casting'; a mold-supporting cup mounted on said box having apassa'ge cornmunicatin'givith the cavity thereof; a screen n the cavity tor preventing sol d material passing into the cylinder casting; a piston in the cylinder casting; and means for actuating said piston.

tig r n. sonwii tz, THOMAS n. SALMON. 

